√2sin(3П/2-х)*sinx=cosx -√2cosx*sinx-cosx=0-cosx(√2sinx+1)=0cosx=0⇒x=π/2+πn,n∈z-5π≤π/2+πn≤-4π-π/2-5π≤πn≤-π/2-4π-5,5≤n≤-4,5n=-5⇒x=π/2-5π=-9π/2sinx=-1/√2x=-π/4+2πk,k∈z U x=5π/4+2πm,m∈z-5π≤-π/4+2πk≤-4π-19/4≤2k≤-15/4-19/8≤k≤-15/8k=-2⇒x=-π/4-4π=--17π/4-5π≤5π/4+2πm≤-4π-25/4≤2m≤-21/4-25/8≤m≤-21/8m=-3⇒x=5π/4-6π=-19π/4x=-19π/4 наим4*(-19π/4):π=-19